You may want to look at Language::Prolog on CPAN. Prolog is another of the rules based languages. I have never used this module so I am not sure how well it is integrated with Perl. Prolog itself is pretty good if you can twist your head around the rules-based stuff (which it looks like you already know).

I've been learning to use Prolog in the last 2 weeks and yes, it's quite different to use rules based languages. You are right, you have to be able to twist your head around to understand rules-based stuff!
Great food program btw, i'll use it next time i try some chicken recipes :)